Hi Clemens
I have been testing something similar in other board (YSE5250-Exynos5). First you must guarantee that the UART device driver is compatible with the hardware or you must write an specific device driver. I have tried to make a GPS device driver using the S3C2410 UART based on the serial-drv package. To connect the uart on the user land with my server i have configured the HW.Device in a vbus with the IO server using this configuration:
-- File: yse5250.devs
local Hw = Io.Hw local Res = Io.Res Io.hw_add_devices { UART3 = Hw.Device { hid = "UART3"; Res.irq(86); Res.mmio(0x12C30000, 0x12C3ffff); } }
To create the vbus, i have created the file yse5250.io:
-- File: yse5250.io
Io.add_vbusses { -- Create a virtual bus for a client and give access to UART3 uart03 = Io.Vi.System_bus(function () dev = wrap(Io.system_bus():match("UART3")); end); }
To run my server using the UART3 on the vbus have used this configuration
-- gps-drv.cfg
-- Run GPS Driver for YSE5250 (Exynos 5250) require("L4"); -- Shortcuts local ld = L4.default_loader; local vbus_uart03 = ld:new_channel(); local platform_ctl = ld:new_channel(); local gps_srv = ld:new_channel(); -- Start the IO Server ld:start( { caps = { sigma0 = L4.cast(L4.Proto.Factory, L4.Env.sigma0):create(L4.Proto.Sigma0); icu = L4.Env.icu; platform_ctl = platform_ctl:svr(); uart03 = vbus_uart03:svr(); }, log = { "IO Server", "green" }, l4re_dbg = L4.Dbg.Warn, }, "rom/io rom/yse5250.devs rom/yse5250.io"); -- Start the GPS Driver Server conected to UART3 ld:start( { caps = { gps_srv = gps_srv:svr(); vbus = vbus_uart03; }, log = {"GPS Driver","blue"} }, "rom/gps_drv");
The server code is very similar to:
/pkg/serial-drv/server/src/main.cc
But in my case i have adjusted the UART to use the S3C2410 uart.
Best regards
On 04/18/2015 06:00 AM, l4-hackers-request@os.inf.tu-dresden.de wrote:
Message: 1 Date: Fri, 17 Apr 2015 12:03:46 +0200 From: "Pflaum, Clemens"clemens.pflaum@mytum.de To:l4-hackers@os.inf.tu-dresden.de Subject: Using a second UART to control a serial device Message-ID:4a79357eec3b3359e8b09e16a3fe0994@roundcube.lrz.de Content-Type: text/plain; charset=US-ASCII; format=flowed
Hi L4 Hackers, Im currently running Fiasco.OC with L4Re on my BananaPi. I'm trying to control a serial device (Pololu Servo Controller) by sending a small series of Bytes over a second UART ( not UART 0 since im getting the console from there ). Via documentation I've found out that UART 3 is at 0x01C28C00 and is a U6_16550A, so I'm hoping the driver in /pkg/drivers-frst/uart/src/uart_pxa.cc will be compatible with that. Where and how would I have to go about initiating my UART 3? By writing a new platform for BPi in /pkg/bootstrap/server/src/platform? The function set_stdio_uart(&_uart); made me think its only the "console" UART. Or do I have to instantiate some kind of Hw.Device like the gpio in /pkg/io/config/arm-omap3.devs and put it on a new vBus like in /pkg/io/doc/example.io ?
Or am I thinking way too complicated and it is as simple as editing the /pkg/serial-drv/server/src/main.cc :
bool Serial_drv::init() { int irq_num = 37; // How can i find out what this number refers to/do i have to change it at all? l4_addr_t phys_base = 0x1000a000; // change to 0x01C28C00 #if 0 int irq_num = 74; l4_addr_t phys_base = 0x49020000; #endif l4_addr_t virt_base = 0;
if (l4io_request_iomem(phys_base, 0x1000, L4IO_MEM_NONCACHED,
&virt_base)) { printf("serial-drv: request io-memory from l4io failed.\n"); return false; } printf("serial-drv: virtual base at:%lx\n", virt_base);
L4::Io_register_block_mmio *regs = new
L4::Io_register_block_mmio(virt_base); _uart = new (malloc(sizeof(L4::Uart_pl011))) L4::Uart_pl011(24019200); //change to L4::Uart_pxa(what does this number mean?) _uart->startup(regs);
Thanks for any answers in advance.
Regards, Clemensc...@mytum.de